As the husband of a psychology teacher and the father of 4 grown kids, one of whom is a PhD researcher dealing with sexual development in mammalian fetuses, I am aware of the transgender issues and even have a bit of knowledge about the genetics of it. I too am concerned with accepting the "feelings" of a child or teen with respect to gender. I think, especially today, there can be many underlying issues/concerns that lead a kid to be concerned about their gender identity and pushing or allowing a gender change when young may be inappropriate, even given the fact that there might be some valid underlying genetic basis.
That being said, using the statements of someone who appears unqualified does little to support even my position let alone the position of those who are more, well, uncompromising based on their religious beliefs and unfounded demand for "common sense", when the real issues involve neither religion nor common sense.